Method for transmitting and receiving broadcast signals, and broadcast reception device using said method

ABSTRACT

Disclosed are a method and device for transmitting and receiving broadcast signals. The disclosed reception method comprises a step for extracting second programme table information which indicates the association properties between a plurality of programmes, the programmes being obtained by using a broadcast stream which comprises at least one programme, programme table information which indicates the broadcast stream, and at least one broadcast service, from a received broadcast signal. The method further comprises a step for parsing the broadcast stream by using the extracted programme table information; and a step for acquiring information about the groups to which the plurality of programmes belong by using the extracted second programme table information.

TECHNICAL FIELD

The present disclosure relates to a method and device for transceiving abroadcast signal.

BACKGROUND ART

A digital TV may provide various additional services in addition to itsoriginal function such as its video and audio, and for example, a usermay select a desired program through metadata representing programbroadcasting airtime.

In the case of Advanced Television System Committee (ATSC) digitalbroadcasting, program information is delivered using the Program andSystem Information Protocol (PSIP) standard, and the digital TVinterprets the delivered program information and displays an ElectronicProgram Guide (EPG) on the screen for user's easy selection.

Moreover, a digital TV service using a wire/wireless communicationnetwork is extensively used. The digital TV service provides variousservices, which may not be provided from a related art analog broadcastservice.

For example, in the case of Internet Protocol Television (IPTV) service,i.e., one type of the digital TV service, a user may actively selecttype and viewing time of a program through bi-directional service. TheIPTV service may provide various additional services such as internetsearch, home shopping, and online game on the basis of such abi-directional service.

DISCLOSURE OF THE INVENTION Technical Problem

Embodiments provide a method and device of transceiving a broadcastsignal, which efficiently deliver additional information on broadcastchannels or programs.

Technical Solution

In one embodiment, a method of transmitting a broadcast signal includes:generating a broadcast stream including at least one program, programtable information representing the broadcast stream, and additionalinformation on the broadcast stream; constituting a stream including thebroadcast stream and the program table information; and transmitting theconstituted stream and the generated additional information,respectively, wherein the program table information includes linkinformation for linking the broadcast stream with the additionalinformation.

In another embodiment, a method of receiving a broadcast signalincludes: extracting a broadcast stream including at least one programand program table information representing the broadcast stream, fromthe broadcast signal; obtaining link information for linking toadditional information on a channel or program in the broadcast stream,from the extracted program table information; and receiving theadditional information by using the obtained link information, whereinthe additional information is received using at least one of NRT serviceand Internet service.

In further another embodiment, a device for receiving a broadcast signalincludes: a receiver for receiving the broadcast signal; a demodulatorfor demodulating the received broadcast signal; a demultiplexer forextracting a broadcast stream including at least one program and programtable information representing the broadcast stream, from thedemodulated broadcast signal; a controller for obtaining linkinformation for linking to additional information on a channel orprogram in the broadcast stream by using the extracted program tableinformation; and a network interface unit for receiving the additionalinformation through an access to an Internet service corresponding tothe obtained link information.

In still further another embodiment, a method of receiving a broadcastsignal includes: extracting a broadcast stream including at least oneprogram and program table information representing the broadcast stream,from the broadcast signal; obtaining link information from the extractedprogram table information; receiving additional information on a channelor program in the broadcast stream by using an NRT service or Internetservice corresponding to the link information; and displaying thereceived additional information.

ADVANTAGEOUS EFFECTS

According to an embodiment, various types of additional information suchas pictures or movies in addition to texts may be efficiently providedby transceiving additional information on broadcast channels or programsthrough a transmission medium such as non-real-time service or Internetservice and constituting link information for a link to the additionalinformation.

Moreover, a user interface environment for easily selecting and playingvarious kinds of additional information may be provided by using thelink information.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a conceptual view illustrating a broadcasting serviceaccording to an embodiment.

FIG. 2 is a block diagram illustrating a configuration of a broadcasttransmitting device according to an embodiment.

FIG. 3 is a block diagram illustrating a configuration of a broadcastreceiving device according to an embodiment.

FIG. 4 is a flowchart illustrating a broadcast signal transmittingmethod according to an embodiment.

FIG. 5 is a view illustrating a configuration of program tableinformation for RT service according to an embodiment.

FIG. 6 is a view illustrating a syntax structure of a Virtual ChannelTable (VCT) shown in FIG. 5 according to an embodiment.

FIG. 7 is a view illustrating a syntax structure of an Event InformationTable (EIT) shown in FIG. 5 according to an embodiment.

FIG. 8 is a view illustrating a data allocation method of a broadcastchannel according to an embodiment.

FIGS. 9 and 10 are views illustrating a configuration of program tableinformation for NRT service.

FIGS. 11 and 12 are views illustrating a syntax structure of a ServiceMap Table (SMT) shown in FIG. 10.

FIG. 13 is a view illustrating a syntax structure of a Non-Real-TimeInformation Table (NRT IT) shown in FIG. 10 according to an embodiment.

FIG. 14 is a block diagram illustrating a method of providing anextended EPG through Internet service.

FIG. 15 is a view illustrating a syntax structure of a link descriptoraccording to an embodiment.

FIGS. 16 to 18 are views illustrating data linkage between the linkdescriptor, VCT, and EIT according to embodiments.

FIGS. 19 to 21 are views illustrating data linkage between the linkdescriptor, VCT, SMT, and NRT IT according to embodiments.

FIG. 22 is a view illustrating a syntax structure of an Extended TextMessage (ETM) location descriptor including link information accordingto an embodiment.

FIG. 23 is a block diagram illustrating a method of receiving abroadcast signal according to a first embodiment.

FIG. 24 is a block diagram illustrating a configuration of a broadcastsignal receiving device according to an embodiment.

FIG. 25 is a flowchart illustrating a method of determining a paththrough which additional information is received according to anembodiment.

FIG. 26 is a block diagram illustrating a configuration of a broadcastsignal receiving device according to an embodiment.

FIG. 27 is a flowchart illustrating a method of receiving a broadcastsignal according to a second embodiment.

FIGS. 27 to 45 are views illustrating a method of displaying on a screenadditional information received using link information according to anembodiment.

MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is a conceptual view illustrating a broadcasting serviceaccording to an embodiment.

Referring to FIG. 1, a TV station 10 may provide Real-Time (RT) serviceand Non-Real-Time (NRT) service to a DTV receiver 20 via a network.

For example, the TV station 10 generates a broadcast signal for RealTime (RT) service according to the Advanced Television Systems Committee(ATSC) adaptive digital broadcasting standard, and then transmit it tothe DTV receiver 20 via a broadcasting network. However, the RT serviceaccording to the present invention is not limited to the ATSC standard,and may be transmitted and received through various broadcastingcommunication standards.

The Non Real Time (NRT) service is a streaming service with which videoand audio contents are streamed from the TV station 10 to the DTVreceiver 20 at a slower speed or a faster speed (or a combination speedthereof) than an RT speed, and may perform an NRT transmitting, storing,or viewing operation, not an RT streaming operation.

The TV station 10 may transmit the RT service or the NRT service via thesame or different channel, and for example, may transmit the RT service,and then, transmit the NRT service using a remaining bandwidth after theRT service transmission or an exclusive bandwidth.

Through the NRT service, the TV station 10 may provide a serviceincluding various contents such as news clip, weather information, VideoOn Demand (VOD), or targeted advertising.

According to an embodiment, the TV station 10 may transmit additionalinformation on broadcast channels or programs through the NRT service,and also may provide various file-based additional information such aspictures, movies, or HTML pages through the NRT service.

In addition, content data transmitted at a lower or faster speed than RTby using the NRT service may be stored in a high capacity storage device(not shown) equipped in the DTV receiver 20 in order to provide them toa user later.

According to an embodiment, the NRT service may be provided in additionto the RT service according to the ATSC adaptive digital broadcastingstandard, but the present invention is not limited thereto.

Additionally, the TV station 10 may provide various Internet servicessuch as VOD, news clip, weather information, or targeted advertising tothe DTV receiver 20 via an IP network such as internet, and may providebi-directional communication between the TV station 10 and the DTVreceiver 20 via the IP network.

For this, the IP network may include an IP service server (not shown)for providing the Internet service, and the IP service server (notshown) may transceive data with a third party server to provideadditional services or advertising links.

According to an embodiment, the TV station 10 may transmit additionalinformation on broadcast channels or programs through the Internetservice, and also may provide various file-based additional informationsuch as pictures, movies, or HTML pages through the Internet service.

Although the broadcasting service according to an embodiment wasdescribed with reference to FIG. 1, the present invention is not limitedthereto. For example, the above mentioned RT service, NRT service, andInternet service may be provided from at least two TV stations, and maybe transmitted to the DTV receiver 20 via at least two differentnetworks.

Additionally, the TV station 10 may not provide at least one of theabove mentioned RT service, NRT service, and Internet service, and mayprovide another type of additional services besides that.

According to an embodiment, in addition to additional informationprovided through the NRT service or Internet service, metadata or adescriptor representing link information for linking the additionalinformation to a corresponding channel or programs may be defined.

FIG. 2 is a block diagram illustrating a configuration of a broadcasttransmitting device. The broadcast transmitting device may include aprogram encoder 100, a PSI and PSIP generator 110, a transportmultiplexer 120, a modulator 130, and a DTV transmitter 140.

Referring to FIG. 2, the program encoder 100 may include a video encoder101, an audio encoder 102, and a SP transport multiplexer 103, and mayoutput a single program transport stream (SP TS) corresponding to oneprogram.

The video encoder 101 receives a video signal of a corresponding programand encodes the video signal through a specific compression, forexample, an MPEG-2 compression algorithm, and then outputs the encodedvideo signal to the SP transport multiplexer 103.

Furthermore, the audio encoder 102 encodes an audio signal of theprogram by using a specific compression, for example, an AC-3compression algorithm, and then outputs the encoded audio signal to theSP transport multiplexer 103.

The SP transport multiplexer 103 multiplexes video data encoded by thevideo encoder 101, audio data encoded by the audio encoder 102,information on a corresponding program, and related data to generate aSP TS.

The PSI and PSIP generator 110 may generate program informationincluding Program Specific Information (PSI) and a Program and SystemInformation Protocol (PSIP).

The PSI may include a Program Association Table (PAT), a Program MapTable (PMT), a Network Information Table (NIT), and a Conditional AccessTable (CAT). The PSIP may include a System Time Table (STT), a MasterGuide Table (MGT), a Virtual Channel Table (VCT), a Rating Region Table(RRT), an Event Information Table (EIT), and an Extended Text Table(ETT).

The PSI and PSIP generator 110 may further generate information oncontents provided through the NRT service or information on contentsprovided through the Internet service.

For example, the PSI and PSIP generator 110 may output a PMT among thegenerated tables to the ST transport multiplexer 103, and may output thePAT and PSIP data to the transport multiplexer 120.

Tables generated by the PSI and PSIP generator 110 may have aconfiguration according to the ATSC adaptive digital broadcastingstandard, and this will be described in detail below.

Moreover, the broadcast transmitting device according to an embodimentmay include a plurality of program encoders 100, and a plurality of SPTSs.

The SP transport multiplexer 120 multiplexes the SP TSs inputted fromthe plurality of program encoders 100 and program information inputtedfrom the PSI and PSIP generator 110, for example, the PAT and PSIP data,to generate a Multi Program (MP) TS.

The modulator 130 modulates the MP TS inputted from the transportmultiplexer 120, and outputs it. For example, the modulation method mayuse an 8-Vestigial Side Band (VSB) according to the ATSC standard.Moreover, the broadcast transmitting device may further include achannel coder.

The DTV transmitter 140 transmits the MP TS outputted from the modulator130 through a specific frequency band. For example, the DTV transmitter140 may transmit the MP TS through a 6 MHz RF channel.

The configuration of the broadcast transmitting device according to anembodiment is described with reference to FIG. 2, but the presentinvention is not limited thereto. Therefore, at least one of componentsshown in FIG. 2 may be omitted, or an additional component may befurther included, if necessary.

For example, moreover, the broadcast transmitting device may furtherinclude components for transmitting a broadcast signal through the NRTservice or Internet service.

FIG. 3 is a block diagram illustrating a configuration of a broadcastreceiving device. The broadcasting receiving device may obtain a videosignal and an audio signal from a broadcast signal received from anexternal by inversely performing the operations of the broadcasttransmitting device described with reference to FIG. 2.

Referring to FIG. 3, the DTV tuner 200 may down-convert a broadcastsignal received via a frequency of a specific physical transport channelthrough an antenna or cable into an Intermediate Frequency (IF)corresponding to a channel that a user selects, and then, may output thedown-converted broadcast signal to a demodulator 210.

The demodulator 210 may demodulate a signal outputted from a tunerthrough a specific modulation, for example, the 8-VSB modulation, andthen may output a TS of an actual bit string.

A demultiplexer 220 may demultiplex the TS inputted from the demodulator210 to extract video stream and audio stream, and for example, maydemultiplex the TS into an MEPG-2 bit stream and AC-3 bit stream.

The demultiplexer 220 may separate program information such as the PSIand PSIP from the TS in order to extract it.

Furthermore, the demultiplexer 220 may output the extracted programinformation, for example, PSIP data, to the program guide database 230.

Moreover, the TS may further include information on contents receivedthrough the NRT service or Internet service, and accordingly, thedemultiplexer 220 may extract the content information from the TS.

A program decoder 240 may decode the video stream and audio streaminputted from the demultiplexer 220 to output video and audio signals ina playback available format, and for this, may further include a videodecoder 241, an audio decoder 242, and an AV synchronizer 243, and adisplay processor 244.

The video decoder 241 decodes a video stream inputted from thedemultiplexer 220 through a specific compression, for example, an MPEG-2compression algorithm, and then outputs the decoded video stream to thedisplay processor 244. Then, the display processor 244 may convert theinputted video signal into displayable various formats for output.

Moreover, the audio decoder 242 may decode the inputted audio streamthrough a specific compression, for example, an AC-3 compressionalgorithm, and then, may output the decoded audio stream.

The AV synchronizer may synchronize the video signal with the audiosignal, which are decoded by the video decoder 241 and the audio decoder242, respectively, by using PCR's from the demultiplexer 220 and timestamps from the video stream.

The configuration of the broadcast receiving device according to anembodiment is described with reference to FIG. 3, but the presentinvention is not limited thereto. Therefore, at least one of componentsshown in FIG. 3 may be omitted, or an additional component may befurther included, if necessary.

For example, moreover, the broadcast receiving device may furtherinclude components for receiving a broadcast signal through the NRTservice or Internet service and processing the received broadcastsignal.

In more detail, the broadcast receiving device may further include anetwork interface unit (not shown) for receiving contents throughInternet service, a display unit (not shown) for playing a video signaloutputted from the program decoder 240, or an audio outputting unit (notshown) for outputting the audio signal.

Hereinafter, a method and device of transmitting a broadcast signal willbe described in detail with reference to FIGS. 4 to 22 according to anembodiment.

FIG. 4 is a flowchart illustrating a method of transmitting a broadcastsignal according to an embodiment, and overlapping contents describedwith reference to FIGS. 1 to 3 will be omitted.

Referring to FIG. 4, a broadcast transmitting device generates abroadcast stream in operation 5300, and generates program tableinformation representing the broadcast stream in operation 5310.

For example, the program encoder 100 in FIG. 2, in more detail, thevideo encoder 101 and the audio encoder 102, may generate and output abroadcast stream including video data and audio data.

The program table information may include tables according to PSI orPSIP generated by the PSI and PSIP generator 110, and an embodimentrelating to the program table information on RT content, i.e., a programprovided through RT service, will be described in detail with referenceto FIGS. 5 to 7.

Additionally, the program table information may include information onNRT content, i.e., a program provided through NRT service, and itsembodiment will be described in detail with reference to FIGS. 9 to 13.

Additionally, the program table information may further includeinformation on internet content, i.e., a program provided throughInternet service.

Then, the broadcast transmitting device generates additional informationon the broadcast stream in operation S320.

For example, the additional information on the broadcast stream may beadditional information on broadcast channels or programs providedthrough RT service, and in more detail, may be represented with variousformats such as pictures, movies, or HTML pages in addition to texts.

In more detail, the additional information may include a thumbnailimage, a background screen, an HTML portal, a preview video, an EPG, ahighlight video, and a multi-view video, which relate to a correspondingTV station, a broadcast channel, or a program.

Additionally, the program table information may be generated in the PSIand PSIP generator 110 of the broadcast transmitting device of FIG. 2.

The broadcast transmitting device constitutes a stream including thegenerated broadcast stream and program table information in operation5330, and then transmits the constituted stream in operation 5340.

For example, the transport multiplexer 120 of the broadcast transmittingdevice of FIG. 2 may multiplex the generated broadcast stream and secondprogram table information in order to generate a TS. Then, the generatedTS may be transmitted through the DTV transmitter 140 after passingthrough the modulator 130.

Then, the broadcast transmitting device transmits the generatedadditional information in operation 5350.

The TS including the broadcast stream and program table information andthe additional information may be transmitted separately, or transmittedusing different transmission methods.

For example, the TS is transmitted using RT service, and the additionalinformation may be transmitted in a file format by using at least one ofNRT service and Internet service.

As the TS and the additional information are separately transmitted,link information for linking the broadcast channel or program toadditional information thereof may be defined.

According to an embodiment, the program table information in the TS mayinclude link information for linking the broadcast channel or program inthe broadcast stream to additional information thereof may be defined.

Accordingly, the link information for linking to the additionalinformation is included in the program table information, and then istransmitted to a broadcast receiving device by using the TS.

FIGS. 5 to 7 are views illustrating tables including information on RTcontent, which is used for describing an embodiment relating to aconfiguration of the program table information.

Table 1 represents tables defined using the PSIP according to the ATSCdigital broadcast standard.

TABLE 1 Table Role MGT Provide version number, size, and PID withrespect to other tables VCT Provide attributes of virtual channels EITProvide information on events of virtual channels ETT Provide detailedinformation on virtual channels and events RRT Provide ratinginformation on a plurality of areas STT Provide date and time

Referring to Table 1 and FIG. 5, the STT may provide information oncurrent date and time and thus, may include time information necessaryfor application that requires synchronization.

Additionally, the RRT may provide rating information, and may defineeffective rating tables with respect to different regions or nations.

The MGT is a pointer for other PSIP tables, and may define a size, PID,and version number for each table.

For example, whether tables are modified may be confirmed by using theversion number and PID of each table in the MGT whose Base-PID is 0xFFB,and accordingly, the modified table may be received.

Furthermore, the VCT may represent virtual channel information necessaryfor channel navigation and tuning, and may include two versions such asa Terrestrial Virtual Channel Table (TVCT) for terrestrial broadcastingand a Cable Virtual Channel Table (CVCT) for cable broadcasting.

For example, the VCT may include as basic information a TS ID, a channelnumber, a short channel name, a program number, an access controllerflag, a location field for Extended Text Message (ETM), and a servicetype, and may consist of syntax as shown in FIG. 6.

In more detail, a broadcast channel defined in the ATSC standard mayinclude a plurality of virtual channels in the VCT consisting of syntaxas shown in FIG. 6. Accordingly, the broadcast receiving device mayrecognize a virtual channel in a corresponding broadcast channel whenreceiving the VCT. Additionally, the virtual channels are respectivelyseparated channels, and may have different source_id for channelidentification.

The EIT includes information on events (i.e., programs) for the virtualchannels in the VCT, and may consist of syntax as shown in FIG. 7.

Additionally, the EIT may classify the events according to each channelby using source_id in the VCT.

Additionally, the EIT may consist of 128 tables, i.e., from EIT-0 to EIT127 corresponding to current events, each having information on programsin a corresponding time interval of every three hours.

The ETT may include relatively long text messages for the events andvirtual channels. For example, each of the VCT and EIT may include oneETT, or may not include the ETT at all.

The Directed Channel Change Table (DCCT) provides definitions formodification requests of virtual channels, and the Directed ChannelChange Selection Code Table (DCCSCT) provides extension for a basicgenre category and location code. The two tables DCCT and DCCSCT may beselective.

FIG. 8 is a view illustrating a data allocation method of a broadcastchannel according to an embodiment.

Referring to FIG. 8, a broadcast channel according to the ATSC standardis modulated through a VSB method of a 6 Mhz band, and a bandwidth ofdata carried on the modulating wave may be about 19.3 Mps. Moreover, thebroadcast channel stream may occupy a bandwidth of about 12 Mbps toabout 13 Mbps, and accordingly, 6 Mps to 7 Mps in the 19.3 Mps may betransmitted as a null packet coded with 0.

The null packet, not a payload, may be used for accurately delivering asystem timer value to a section data area.

Furthermore, the null packet area of 6 Mps to 7 Mps may be used fortransmitting another data in addition to a broadcast channel stream.

According to an embodiment, NRT content data provided through the NRTservice may be transmitted using the remaining bandwidth of 6 Mps to 7Mps, and for this, a Digital Storage Media-Command & Control (DSM-CC)protocol and a File Delivery over Unidirectional Transport (FLUTE)method may be used.

FIGS. 9 to 13 are views illustrating tables including the information onNRT content, which is used for describing another embodiment relating toa configuration of the program table information.

Referring to FIG. 9, a terrestrial VCT (TVCT) may provide information onvirtual channels, and may include service_type representing the NRTservice. For example, the NRT service delivered through an IP packet maybe represented with service_type having a value of 0x08.

Moreover, the TVCT may include program_number and channel_TSIDindicating information in a PAT, and the PAT may indicate a PMT throughprogram_map_pid.

Furthermore, a TS packet corresponding to a PID elementrary_pid in thePMT may include a DSMCC Addressable Section, and may deliver an IPpacket for the NRT service by using the DSMCC Addressable Section.

For example, IP packets for NRT services in one virtual channel may bedelivered as TS packets that respectively correspond to a plurality ofPID values, and IP packets delivered through all DSM-CC addressablesections referred from the PMT may be gathered to constitute one IPsubnet.

Referring to FIG. 10, for the NRT service, the program table informationmay include a Non-Real-Time Information Table (NRT IT), a Service MapTable (SMT), and a FLUTE File Delivery Table.

Moreover, the NRT IT may further include information on NRT contentsreceived through the NRT service and the SMT-MH may be linked to the NRTIT by using a Service ID.

The SMT-MH may be linked to a FLUTE File Delivery Table (FDT) by usingIP dst (i.e., a destination IP address), port (i.e., a port number), anda Transport Session Indicator (TSI).

According to an embodiment, IP dst and port in the SMT-MH may be224.0.23.60:4937, i.e., a Service Signaling Channel (SSC) according tothe ATSC standard.

The SMT-MH may include service-level attributes for NRT services in aTS, and for this, may consist of syntax as shown in FIGS. 11 and 12.

For example, for the NRT service, service category of the SMT-MH may beset with 0x0E.

A content linkage in the NRT IT may correspond to at least one file ofthe FLUTE FDT, and the FLUTE FDT may include Content-Location for eachfile, for example, a Uniform Resource Locator (URL).

Moreover, an icon content-linkage in the SMT-MH or NRT-IT may correspondto a file including a graphic icon in the FDT.

Additionally, it may be linked to a Text Fragment Table (TFT) by using acontent linkage in the NRT-IT, and the TFT may provide text metadata forcorresponding content.

FIG. 13 is a view illustrating syntax of the NRT IT.

Referring to FIG. 13, the NRT-IT may include information on RT contentsuch as a content_name, a content_linkage, duration/expiration,playback_length, or content_length.

The configuration of the program table information for NRT servicedescribed with reference to FIGS. 9 to 13 is just one embodiment, andthus, the present invention is not limited thereto.

For example, the information on NRT service may be delivered through thefollowing method.

Once 0x95 representing the NRT service is delivered as a stream_type toa Service Location Descriptor (SLD) in the TVCT, the broadcast receivingdevice recognizes that a corresponding virtual channel corresponds tothe NRT service.

Additionally, Once 0x95 representing the NRT service is delivered asstream_type to a Service Location Descriptor (SLD) in the TVCT, thebroadcast receiving device recognizes that a corresponding virtualchannel corresponds to the NRT service.

The DST delivers additional information for providing data service, andan association tag for the NRT service may be searched by using theadditional information.

The association tag is connected to one of streams of the PMT, and astream corresponding to the PID that the one indicates may include theinformation on NRT service.

Furthermore, a TS packet corresponding to the PID that the associationtag of the PMT indicates may include a DSMCC Addressable Section, asdescribed with reference to FIG. 9.

According to an embodiment, a broadcast transmitting device may transmitadditional information on a broadcast channel or program throughInternet service.

FIG. 14 is a view illustrating a method of providing an extended EPGthrough Internet service.

Referring to FIG. 14, an SI parser 250 of a broadcast transmittingdevice parses program table information, for example, PSI and PSIPtables, received through a DTV tuner 200, and outputs EPG information byparsing an EIT.

Moreover, a network interface unit 260 is connected to internet by usingEthernet TCP/IP, and receives additional information provided throughInternet service.

An HTML/XML parser 270 parses the additional information receivedthrough the network interface unit 260 in order to output EGPinformation.

EPG information obtained from the program table information receivedthrough the DTV tuner 200 and EGP information obtained from theadditional information received through the network interface unit 260are combined to constitute an internet-extended EPG.

FIG. 15 is a view illustrating a syntax structure of a link descriptoraccording to an embodiment.

The link descriptor is included in the program information table so thatit may represent link information for linking a broadcast channel orprogram to additional information thereof.

Referring to FIG. 15, descriptor_tag in the link descriptor defines atag of a corresponding descriptor, and descriptor_length represents thelength of a corresponding descriptor.

Additionally, number_of_links represents the number of links to acorresponding channel or program.

For example, if there are as additional information for a specificprogram a thumbnail image provided through NRT service and a previewvideo provided through Internet service, the two additional informationare defined each with one link, and accordingly, number_of_links becomes“2”.

link_type represents that what information is included in acorresponding link, i.e., types of additional information according to acorresponding link, and may have values as shown in Table 2.

TABLE 2 link_type Html portal 0 × 01 Thumbnail 0 × 02 Preview clip 0 ×03 EPG 0 × 04 Highlight 0 × 05 Multiview 0 × 06

Referring to Table 2, the types of corresponding additional informationrepresented by link_type may be one of an Html Portal, a thumbnail, apreview clip, an EPG, a highlight image, and a multiview image. “0x00”,“0x01”, “0x02”, “0x03”, “0x04”, “0x05”

“0x06” may be assigned to the six link types, respectively.

link_media represents that which path is used when a corresponding linkis delivered, and that is, may represent a media corresponding to a paththrough which the additional information is received.

Moreover, link_byte represents the ID of a corresponding link, andlink_length represents the length of link_byte.

Since the ID of a link for accessing each media that receives theadditional information may be different, link_length and link_byte maybe designated to identify this.

Table 3 represents link_media and link_byte designated for each mediathat provides the additional information according to an embodiment.

TABLE 3 link_media link_byte NRT service 0 × 02 service_id, content_idInternet service 0 × 03 URL

Referring to Table 3, link_media having 0x02 and 0x03 may berespectively designated for NRT service and Internet service, whichprovide the additional information.

Additionally, additional information provided through NRT service may bedesignated as link_byte by using service_id of the NRT service andcontent_id of NRT content including the additional information.

Additionally, additional information provided through Internet servicemay be designated as link_type by using a URL for downloading theadditional information.

Moreover, content_id may correspond to content_linkage orcontent_name_text( ) of the NRT IT described with reference to FIG. 13.

A broadcast channel or program may be linked to an NRT IT of additionalinformation transmitted through NRT service by using link_byte.

Additionally, when the additional information is transmitted throughInternet service, the broadcast receiving device may access to a serverby using a URL, i.e., link_byte of a corresponding link, and then,download corresponding additional information.

According to an embodiment, when new additional information transmissionmedium is added in addition to the NRT service and Internet service, anew value for link_media besides “0x02”

“0x03” may be added.

mime_type of the link descriptor represents an expression type of acorresponding link, and mime_type_length represents the length ofmime_type.

For example, mime_type represents that additional informationcorresponds to which type of video, text, and image, and represents anextension of a file including the additional information in addition tothat.

Moreover, description represents detailed information on a correspondinglink, and description_length represents the length of the description.

For example, the description may include the title of correspondingadditional information and description thereof.

According to an embodiment, link descriptor According to an embodiment,the link descriptor described with reference to FIG. 15 may be includedin the program table information, and for example, may be included in aVCT or an EIT.

FIGS. 16 to 18 are views illustrating data linkage between the linkdescriptor, VCT, and EIT when the additional information is transmittedthrough Internet service according to embodiments.

Referring to FIG. 16, by using a first virtual channel in a VCT, i.e.,source_id of “VCH0”, EIT0 and EIT1 having source_id of “VCH0” may beconnected.

Additionally, by using each program table information in the EIT0 andEIT1, it is recognized that there are four programs “EVENT0”, “EVENT1”,“EVENT2”, and “EVENT3” provided to the virtual channel “VCH0” through RTservice.

Moreover, a link descriptor may be included in additional_descriptors ofthe VCT.

Since the additional descriptor represents information on MUX or aphysical channel corresponding to the VCT, additional information on theMUX or physical channel may be provided through Internet serviceconnected using the link descriptor.

For example, the additional information on MUX may be information on aTV station that transmits corresponding MUX, and in more detail, mayinclude a broadcaster logo or a URL of a broadcaster homepage.

Furthermore, a URL of Internet service that provides additionalinformation on the MUX or physical channel may be designated by thelink_byte of the link descriptor.

Additionally, when a virtual channel identifier source_id is added to anURL in link_byte, additional information on a corresponding virtualchannel may be provided through Internet service.

For example, as shown in FIG. 16, when a URL is designated with“http://xxx/yyy.html?source_id=VCH0” in the link descriptor, additionalinformation on a virtual channel “VCH0” corresponding to source_id maybe provided through Internet service of a corresponding URL.

When a broadcast program identifier event_id is added to a URL inlink_byte, additional information on a corresponding program may beprovided through Internet service.

For example, as shown in FIG. 16, when a URL is designated with“http://xxx/yyy.html?source_id=VCH0&event_id=EVENT0” in the linkdescriptor, additional information on the program “EVENT0” correspondingto event_id may be provided through Internet service of a correspondingURL.

Referring to FIG. 17, the link descriptor may be included in descriptorsof the VCT.

Since the descriptor represents information on a corresponding physicalchannel, additional information on the virtual channel may be providedthrough Internet service connected using the link descriptor.

For example, the additional information on the virtual channel mayinclude a virtual channel logo or a channel homepage.

As shown in FIG. 17, when a URL is designated with “http://xxx/yyy.html”in the link descriptor, additional information on a virtual channel“VCH0” having the link descriptor may be provided through Internetservice having the URL.

Moreover, when a broadcast program identifier event_id is added to a URLin link_byte, additional information on a corresponding program may beprovided through Internet service.

For example, as shown in FIG. 17, when a URL is designated with“http://xxx/yyy.html?event_id=EVENT0” in the link descriptor, additionalinformation on the program “EVENT0” corresponding to event_id may beprovided through Internet service of a corresponding URL.

Referring to FIG. 18, the link descriptor may be included in descriptorsof the EIT.

Since the descriptor of the EIT represents information on acorresponding event, additional information on a broadcast program maybe provided through Internet service connected using the linkdescriptor.

For example, the additional information on a broadcast program mayinclude an HTML page, a thumbnail image, a highlight video, a previewvideo, a multiview video, or detailed information, which relate to thecorresponding broadcast program.

As shown in FIG. 18, when a URL is designated with “http://xxx/yyy.html”in the link descriptor, additional information on a broadcast program“EVENT0” having the link descriptor may be provided through Internetservice having the URL.

FIGS. 19 to 21 are views illustrating data linkage between the linkdescriptor, VCT, and SMT when the additional information is transmittedthrough NRT service according to embodiments.

Referring to FIG. 19, with the link descriptor in additional_descriptorsof the VCT, additional information on MUX or a physical channel may beprovided through NRT service connected using the link descriptor.

Furthermore, service_id and content_id of the NRT service providing theadditional information on MUX or a physical channel may be designated bythe link_byte of the link descriptor.

For example, when service_id is designated with “0x0C50” and content_idis designated with “id0” in link_byte, a File of a FLUTE sessioncorresponding to service_id and content_id may be connected through anSMT and an NRT IT.

The File transmitted using the NRT service may include the additionalinformation on MUX or a physical channel.

Referring to FIG. 20, with the link descriptor in descriptors of theVCT, additional information on a corresponding virtual channel may beprovided through NRT service connected using service_id and content_idof the link descriptor.

Referring to FIG. 21, the link descriptor may be included in descriptorsof the EIT, so that additional information on a corresponding broadcastprogram may be provided through NRT service.

FIG. 22 is a view illustrating a syntax structure of an Extended TextMessage (ETM) location descriptor including link information, andillustrating a method of extending ETM_location in a VCT or an EIT.

ETM_location represents whether there is an ETT that delivers detailedinformation on a broadcast channel or program in a plain text format.

According to an embodiment, extending ETM_location may deliver theadditional information on a broadcast channel or program through NRTservice or Internet service.

For example, ETM_location_extension_descriptor shown in FIG. 22 mayfollow ETM_location that is to extend in the VCT or EIT.

Referring to FIG. 22, descriptor_tag inETM_location_extension_descriptor defines a tag of a correspondingdescriptor, and descriptor_length represents the length of acorresponding descriptor.

ETM_in_PTC_carrying_this_PSIP represents that an ETT is included in a TSthrough which a corresponding table was received, and has the same valueas “0x01” of ETM_location.

Moreover, ETM_in_PTC_specified_by_the_channel_TSID represents that anETT is included in a TS through which a corresponding channel isreceived, and has the same value as “0x02” of ETM_location.

Moreover, ETM_in_NRT_service represents that the above additionalinformation is provided through NRT service, and ETM_in_Internet_servicerepresents that the above additional information is provided throughInternet service.

mime_type of the link descriptor represents a format, i.e., anexpression type of additional information, and mime_type_lengthrepresents the length of mime_type.

link_length represents service_id and content_id in the case of a linkfollowing link_length, i.e., NRT service, and the length of a URL in thecase of Internet service.

service_id represents an identifier of service described in an SMT inrelation to NRT service that transmits the additional information, andcontent_id represents an identifier of content described in an NRT-IT.

Moreover, a URL represents the position of Internet service thattransmits the additional information.

Hereinafter, a broadcast signal receiving method and device according toan embodiment will be described in more detail with reference to FIGS.23 to 26.

The broadcast signal receiving method may be obtained through inverseoperations of the broadcast signal transmitting method described withreference to FIGS. 4 to 22, and thus, overlapping descriptions will beomitted.

FIG. 23 is a flowchart illustrating a method of receiving a broadcastsignal according to a first embodiment, and its description is made inrelation to a block diagram of a broadcast receiving device shown inFIG. 24.

Referring to FIG. 23, a receiver 500 of the broadcast receiving devicereceives a broadcast signal in operation S400, and a demultiplexer 520extracts a broadcast stream and program table information from thereceived broadcast signal in operation 5410.

Additionally, the received broadcast signal is demodulated by thedemodulator 510, and then, is inputted to the demultiplexer 520. Then, adecoder (not shown) decodes the extracted program table information andoutputs it to a controller 540. Then, the broadcast stream may be parsedusing the extracted table information.

Then, the controller 540 obtains link information from the extractedprogram table information in operation S420, and the receiver 500 or anetwork interface unit 540 receives additional information by using theobtained link information in operation 5430.

For example, when the additional information is provided through NRTservice, the receiver 500 may receive the additional information inaddition to the broadcast signal, and the received additionalinformation may be stored in a high capacity storage medium (not shown).

Additionally, when the additional information is provided throughInternet service, the network interface unit 540 accesses an internetserver to receive the additional information.

Additionally, the program table information may include tables such asthe MGT, VCT, EIT, ETT, RRT or STT described with reference to FIGS. 5to 7, or tables for NRT service such as the SMT, NRT IT, FDT or TFTdescribed with reference to FIGS. 9 to 13.

According to another embodiment, a path through which the additionalinformation is received may be determined by the content of a linkinformation related descriptor, an internet access of a broadcastreceiving device, and reception availability of NRT content.

FIG. 25 is a flowchart illustrating a method of determining a paththrough which additional information is received according to anembodiment.

Referring to FIG. 25, when a receiver 500 of a broadcast receivingdevice receives a VCT or an EIT in operation 5600, a controller 530confirms whether there is an ETM extension in the received VCT or EIT inoperation 5610.

For example, the ETM extension may be provided usingETM_location_extension_descriptor described with reference to FIG. 22.

If there is the ETM extension, the controller 530 parses a correspondingETM extension descriptor in operation 620, and then confirms that thereis a URL in operation 5630.

If there is the URL in the ETM extension descriptor, the controller 530confirms whether the broadcast receiving device is connected to internetthrough the network interface unit 540 in operation 5640.

If the broadcast receiving device is connected to internet, a path forreceiving the additional information is determined by receiving theadditional information through Internet service in operation 5650

Additionally, if there is no URL in the ETM extension descriptor or thebroadcast receiving device is not connected to internet, the controller530 confirms whether there is NRT service in operation 5660.

For example, the controller 530 confirms whether there are service_idand content_id in the ETM extension descriptor in order to confirmwhether there is an NRT service providing additional information.

If there is the NRT service, the controller 530 confirms whether the NRTservice is available for downloading in operation 5670, and ifdownloadable, determines that the additional information is received byusing the NRT service in operation 5680.

Additionally, if there is no NRT service or the NRT service isunavailable, the controller 530 confirms whether ETM Loc, i.e., an ETMlocation, has a value of “1” or “2” in operation 5700.

If ETM Loc has “0”, there is no ETT; if it has “1”, the ETT is includedin a TS through which a corresponding table was received; and if it has“2”, the ETT is included in a TS through which a corresponding channelis received.

Accordingly, when ETM Loc has “1” or “2”, it is indicated that there isan ETT having detailed information on a corresponding broadcast channelor program.

Accordingly, when ETM Loc has “1” or “2”, the controller 530 obtains thedetailed information on a corresponding broadcast channel or programfrom the ETT in operation 5710.

As described with reference to FIG. 25, the reception path of theadditional information may be determined with a priority in the order ofInternet service, NRT service, and ETT.

FIG. 26 is a view illustrating a configuration of a broadcast signalreceiving device according to another embodiment, and overlappingcontents described with reference to FIGS. 3 and 24 will be omitted.

Referring to FIG. 26, a demodulator 810 demodulates a broadcast signalreceived though a turner 800, and a demultiplexer 820 demultiplexes a TSinputted from the demodulator 810 to extract a broadcast stream andprogram table information.

Additionally, the tuner 800 may receive additional information providedthrough NRT service in additional to the RT broadcast signal.

A table information decoder 830 decodes the extracted program tableinformation and outputs it to a controller 851.

Additionally, a network interface unit 840 may transceive data inconnection to a wire/wireless network such as internet. For example, thenetwork interface unit 840 may access an internet server with a URL, andthen, may download additional information provided through Internetservice.

For this, the network interface unit 840 may include a wireless networkPhy and MAC.

A controller 851 of a signal processor 850 parses a broadcast streaminputted from the demultiplexer 820 by using the decoded first programtable information, for example, a PSI and PSIP table, to output videostream and audio stream.

Additionally, the controller 851 processes content data inputted fromthe network interface unit 840, and output the processed content data toan AV decoder 852.

The AV decoder 852 decodes and outputs the video stream and audio streaminputted from the controller 851; a display unit 870 displays an imageby using the decoded video data; and a speaker 875 outputs audio byusing the audio data.

According to an embodiment, the controller 851 may obtain linkinformation for linking to the additional information from the decodedprogram table, for example, a VCT or an EIT.

Moreover, the controller 851 may include a broadcast processor (notshown) for processing a broadcast stream inputted from the demultiplexer820, and a broadband processor (not shown) for processing content datainputted from the network interface unit 840, and may further include achannel manager (not shown) and an application manager (not shown)beside those.

Additionally, the signal processor 850 may further include an internalmemory (not shown), an internal DMR module (not shown) for communicatingwith an external DRM module, a PVR/Progressive download unit (notshown), and an input device (not shown).

A memory 860 may include ROM, RAM, and NVRAM, and may store the firstand second program table information.

The broadcast receiving device may include a high capacity storagemedium 880, and for example, the high capacity storage medium 880 maystore contents received through NRT service.

Furthermore, a remote controller 890 may control an operation of thebroadcast receiving device at a user's input.

FIG. 27 is a view illustrating a method of receiving a broadcast signalaccording to a second embodiment, and overlapping contents describedwith reference to FIGS. 23 and 26 will be omitted.

Referring to FIG. 27, the broadcast receiving device extracts abroadcast stream and program table information from the receivedbroadcast signal in operation 5910, and obtains link information fromthe extracted program table information in operation 5910.

Then, the broadcast receiving device displays a button for playingadditional information by using the obtained link information inoperation 5930.

For example, if the additional information is a highlight video for aspecific program, the controller 851 confirms that there is a highlightvideo in the additional information by using the link information, andaccordingly, controls a display unit 870 to display a button forallowing a user to select playing of the highlight video.

When a user selects the display button in operation S930, the broadcastreceiving device receives the additional information through NRT serviceor Internet service corresponding to the link information in operation5940, and then plays and displays the received additional information inoperation 5950.

Hereinafter, a configuration of a user interface (UI) displaying on ascreen additional information received through the link information willbe described in detail with reference to FIGS. 28 to 45.

FIG. 28 is a view illustrating an example of the link information. FIG.29 is a view illustrating an example of a UI displaying additionalinformation received using the link information.

Referring to FIG. 28, there may be an ETT that provides detailedinformation consisting of text on “EVENT0” i.e., a program of a virtualchannel “VCH0”, and a link descriptor that represents additionalinformation provided through NRT service and Internet service.

Moreover, the Link Descriptor may include two links “Link0” and “Link1”.Additional information linked using “Link0” is a thumbnail image “jpg”file, which has content_id of “id0” and is provided through an NRTservice having service_id of “0x0C50”.

Additionally, the additional information linked using “Link1” is apreview video “avi” file, which is provided through Internet servicehaving a URL of http://xxx/yyy.avi.

Referring to FIG. 29, a thumbnail image 1010 received through an NRTservice corresponding to “Link0” of the link descriptor may be displayedon a screen 1000 of the broadcast receiving device, and the displayedthumbnail image 1010 may be an image representing a title of thecorresponding program “EVENT0”.

Additionally, a “PREVIEW” button 1020 for playing a preview videoaccording to “Link1” of the link descriptor may be displayed on thescreen 1000.

When a user selects the “PREVIEW” button 1020, the network interfaceunit 840 of the broadcast receiving device accesses http://xxx/yyy.avii.e., a URL of “Link1” to download the preview video file throughInternet service, and then, the downloaded preview video file may beplayed on the screen 1000.

Moreover, the detailed information 1030 in a text form may be displayedon the screen 1000 by using the ETM of ETTO shown in FIG. 28.

FIGS. 30 and 31 are views illustrating a method of configuring anadditional information screen by using the link information.

Referring to FIG. 30, a Link Descriptor may include three links “Link0”,“Link1”, and “Link2”. Additional information linked using “Link0” isprovided through an NRT service having service_id of “0x0000”, and is atext “html” file of html_portal having content_id of “0x00000000”.

Moreover, additional information linked using “Link1” is providedthrough an NRT service having service_id of “0x0000”, and is an image“png” file of a thumbnail type having content_id of “0x00000001”.

Additionally, the additional information linked using “Link2” isprovided through Internet service having a URL of“www.heroes.com/preview.avi”, and is a video “avi” file of a previewtype.

If the broadcast receiving device has a webbrowsing function, itreceives an HTML page of “Link1” among the three links, and thenconfigures an additional information screens shown in FIG. 30 by usingthe received HTML page.

According to the HTML page shown in FIG. 30, a “back.jpb” image fileconstituting a background screen 1100 is received through Internetservice, and “logo.png” constituting a log image 1110 of a correspondingprogram is received through NRT service corresponding to “Link1”.

Furthermore, “logo.png” may be received through Internet service byusing a URL of the HTML page.

When a user selects a “PREVIEW” button 1120, a “preview.avi” video fileconstituting a preview video may be received through Internet service byusing a URL of the HTML page.

Referring to FIG. 31, if a broadcast receiving device has no webbrowsingfunction, it cannot display the HTML page, but may receive additionalinformation by using other links such as “Link1” and “Link2”.

In this case, the broadcast receiving device displays detailedinformation 1030 by using an ETT, and configures an additionalinformation screen by using remaining links except for a link of theHTML page in the link descriptor.

For example, “logo.png” constituting the logo image 1110 is receivedthrough an NRT service corresponding to “Link1”, and a button 1020 forplaying a preview video by using “Link2” may be displayed on a screen1000.

FIGS. 32 to 37 are views illustrating a method of displaying a highlightimage by using link information according to embodiments when ahighlight image of sports events through NRT service or Internetservice.

Referring to FIG. 32, there are links for two highlight images such as“Link0” and “Link1” in a Link Descriptor.

Moreover, a highlight image connected using “Link0” is an “avi” filethat has content_id of “0x00000003”, is provided through an NRT servicehaving service_id of “0x0000”, and has an image title of “Radoncic(first half 28 min)”.

Moreover, a highlight image connected using “Link1” is an “avi” filethat has content_id of “0x00000004”, is provided through an NRT servicehaving service_id of “0x0000”, and has an image title of “Thiago (secondhalf 28 min)”.

Referring to FIG. 33, when a user requests displaying of additionalinformation while watching a broadcast program, an additionalinformation window 1200 for displaying additional information on acorresponding program may be displayed on an image 1210 of the broadcastprogram.

“K-league final”, i.e., the title of the corresponding program, anddetailed information 1240 may be displayed on the additional informationwindow 1200 by using an EIT or ETT.

Additionally, as it is confirmed that there are two highlight imagesaccording to the link information shown in FIG. 33, buttons 1220 and1230 for playing the two highlight images may be displayed on theadditional information window 1200.

In this case, “Radoncic (first half 28 min)” designated in thedescription of “Link0” may be displayed as a title on the first button1220 for playing a highlight image of “Link0”, and “Thiago (second half28 min)” designated in the description of “Link1” may be displayed as atitle on the second button 1230 for playing a highlight image of“Link1”,

Referring to FIG. 34, when a user selects the first button 1220, ahighlight image 1250 of “Radoncic (first half 28 min)” corresponding tothe first button 1220 may be played in a partial area of the additionalinformation window 1200.

In this case, the image 1210 of the RT broadcast program is played as itis if the additional information window 1200 does not cover the entirescreen 1000, and only the highlight image 1250 is played if theadditional information window 1200 covers the entire screen 1000.

Referring to FIG. 35, when a user selects the first button 1220, theadditional information window 1200 disappears, and the highlight image1250 may be displayed on the image 1210 of the RT broadcast program inPicture In Picture (PIP).

Referring to FIG. 36, when a user selects the first button 1220, theadditional information window 1200 disappears, and the highlight image1250 is displayed on the entire screen 1000. Accordingly, watching theRT broadcast may be stopped.

Referring to FIG. 37, when a user selects the first button 1220, theadditional information window 1200 disappears; the highlight image 1250is displayed on the entire screen 1000; and the image 1210 of the RTbroadcast program is displayed on the highlight image 1250 in PIP.

When images are displayed in PIP as shown in FIG. 35 or 37, one or bothsound of the RT broadcast and sound of the highlight image may beoutputted at a user's selection using a remote controller 890.

FIGS. 38 to 43 are views illustrating a method of displaying a multiviewimage by using link information according to embodiments, when amultiview image captured at a different view point than a view point ofan RT broadcast is displayed through NRT service or Internet serviceduring watching a sports event.

Referring to FIG. 38, there are links for two multiview images such as“Link0” and “Link1” in a Link Descriptor.

A multiview image connected using “Link0” is an “avi” file providedthrough Internet service having a URL of “www.racing.com/racer.avi” andincludes view point related information of “Racer #10”.

A multiview image connected using “Link0” is an “avi” file providedthrough Internet service having a URL of “www.racing.com/finish.avi” andincludes view point related information of “Finish Line”.

Referring to FIG. 39, when a user requests displaying of additionalinformation during watching a broadcast program, an additionalinformation window 1300 for displaying the additional information may bedisplayed on an image 1310 of the program.

“Formula one” i.e., the title of the corresponding program, and detailedinformation 1340 may be displayed on the additional information window1300 by using an EIT or ETT.

Additionally, as it is confirmed that there are two multiview imagesaccording to link information as shown in FIG. 38, buttons 1320 and 1330for playing the two multiview images may be displayed on the additionalinformation window 1300.

In this case, “Racer #10” designated in the description of “Link0” maybe displayed as a view point of a corresponding image on the firstbutton 1320 for playing the multiview image of “Link0”, and “FinishLine” designated in the description of “Link1” may be displayed as aview point of a corresponding image on the second button 1330 forplaying the multiview image of “Link1”.

Referring to FIG. 40, when a user selects the first button 1320, themultiview image 1350 captured at a view point of “Racer #10”corresponding to the first button 1320 may be played in a partial areaof the additional information window 1300.

In this case, the image 1310 of the RT broadcast program is played as itis if the additional information window 1300 does not cover the entirescreen 1000, and only the multiview image 1350 is played if theadditional information window 1300 covers the entire screen 1000.

Referring to FIG. 41, when a user selects the first button 1320, theadditional information window 1300 disappears, and the multiview image1350 may be displayed on the image 1310 of the RT broadcast program inPIP.

Referring to FIG. 42, when a user selects the first button 1320, theadditional information window 1300 disappears, and the multiview image1350 is displayed on the entire screen 1000. Accordingly, watching theRT broadcast may be stopped.

Referring to FIG. 43, when a user selects the first button 1320, theadditional information window 1300 disappears; the multiview image 1350is displayed on the entire screen 1000; and the image 1310 of the RTbroadcast program is displayed on the multiview image 1350 in PIP.

When images displayed in PIP as shown in FIG. 41 or 43, one or bothsound of the RT broadcast and sound of the multiview image may beoutputted at a user's selection using a remote controller 890.

FIGS. 44 and 45 are views illustrating a method of displaying an EPG byusing link information according to an embodiment when the EPG isdisplayed through NRT service or Internet service.

Referring to FIG. 44, there are two links for an EPG “Link0” and “Link1”in a Link Descriptor.

Additional information linked using “Link0” is provided through an NRTservice having service_id of “0”, and is a thumbnail image “jpg” filehaving content_id of “0”.

Additionally, additional information linked using “Link1” is an EPG“html” file provided through an Internet service having a URL of“http://xxx/yyy.html”.

Once it is confirmed that internet is connected and there is an EPG link“Link1” in an HTML format as shown in FIG. 44, an EPG may be displayedon a screen by using an HTML page corresponding to “Link1”.

Referring to FIG. 45, a thumbnail image 1410 according to “Link0” isreceived through the NRT service, and then, is displayed on a screen1000. The thumbnail image 1410 may be the log of a correspondingbroadcaster.

Moreover, an EPG 1400 expressed using an HTML according to “Link1” maybe displayed on an entire or portion of the screen 1000.

Additionally, if there is a link in the EPG 1400 for reading additionalinformation on each program into another page, a specific program may behighlighted using direction keys in a remote controller 890, and a newHTML page may be provided according to a link representing additionalinformation on the highlighted program.

In this case, a URL address of a previous page may be stored, and when auser selects a previous page button 1420, it may return to a previousscreen by using the stored URL address.

Moreover, the next page button 1430 is activated when a user selects theprevious page button 1420, and the page before a user selects theprevious page button 1420 is displayed on the screen 1000 when a userselects the next page button 1430.

According to the method described with reference to FIGS. 44 and 45, EPGinformation is received through NRT service or Internet service withoutreceiving an EIT, and then, is displayed on the screen 1000.

A broadcast signal receiving method according to an embodiment can bestored in a computer readable recording medium. Examples of the computerreadable recording medium include read-only memory (ROM), random-accessmemory (RAM), CD-ROMs, magnetic tapes, floppy disks, and optical datastorage devices.

The computer readable recording medium can also be distributed overnetwork coupled computer systems so that the computer readable code isstored and executed in a distributed fashion. Also, functional programs,codes, and code segments for accomplishing the present invention can beeasily construed by programmers skilled in the art to which the presentinvention pertains.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure.

1. A method of transmitting a broadcast signal, comprising: generating abroadcast stream including at least one program, program tableinformation representing the broadcast stream, and additionalinformation on the broadcast stream; constituting a stream including thebroadcast stream and the program table information; and transmitting theconstituted stream and the generated additional information,respectively, wherein the program table information comprises linkinformation for linking the broadcast stream with the additionalinformation.
 2. The method according to claim 1, wherein the constitutedstream is transmitted using Real Time (RT) service, and the additionalinformation is transmitted using at least one of Non-Real Time (NRT)service and Internet service.
 3. (canceled)
 4. The method according toclaim 3, wherein the additional information comprises at least one of apicture and video related to the channel or program.
 5. The methodaccording to claim 1, wherein the program table information comprises aVirtual Channel Table (VCT); and the VCT comprises the link informationfor linking to additional information on a corresponding channel or aprogram of a corresponding channel.
 6. The method according to claim 1,wherein the program table information comprises an Event InformationTable (EIT), and the EIT comprises the link information for linking toadditional information on a corresponding program.
 7. The methodaccording to claim 1, wherein when the additional information istransmitted using Internet service, the link information comprises aUniform Resource Locator (URL) corresponding to the additionalinformation.
 8. The method according to claim 1, wherein the programtable information comprises a Service Map Table (SMT) and an NRTInformation Table (NRT IT) representing information on a contenttransmitted through NRT service; and when the additional information istransmitted through the NRT service, the link information comprise aservice ID of the SMT and a content ID of the NRT IT corresponding tothe additional information.
 9. The method according to claim 1, whereinthe link information comprises information on types of the additionalinformation; and the types of the additional information comprises atleast one of an HTML page, a thumbnail image, a preview image, a programguide, a highlight image, and a multiview image.
 10. (canceled)
 11. Amethod of receiving a broadcast signal, comprising: extracting abroadcast stream including at least one program and program tableinformation representing the broadcast stream, from the broadcastsignal; obtaining link information for linking to additional informationon a channel or program in the broadcast stream, from the extractedprogram table information; and receiving the additional information byusing the obtained link information, wherein the additional informationis received using at least one of NRT service and Internet service. 12.The method according to claim 11, wherein the obtaining of the linkinformation comprises obtaining the link information from at least oneof a VCT and an EIT in the program table information.
 13. The methodaccording to claim 12, if there is no link information in at least oneof the VCT and the EIT, further comprising obtaining detailedinformation on the channel or program by using an Extended Text Table(ETT).
 14. The method according to claim 11, wherein the Internetservice has a higher priority than the NRT service, with respect to apath through which the additional information is received.
 15. Themethod according to claim 11, wherein the receiving of the additionalinformation comprises receiving the additional information through anaccess to Internet service by using a URL in the link information. 16.The method according to claim 11, wherein the receiving of theadditional information comprises: linking to an NRT IT representing theadditional information by using a service ID and content ID in the linkinformation; and receiving an NRT content including the additionalinformation by using the linked NRT IT.
 17. The method according toclaim 11, wherein the link information comprises information on types ofthe additional information; and the types of the additional informationcomprises at least one of an HTML page, a thumbnail image, a previewimage, a program guide, a highlight image, and a multiview image. 18.(canceled)
 19. (canceled)
 20. A device for receiving a broadcast signal,comprising: a receiver for receiving the broadcast signal; a demodulatorfor demodulating the received broadcast signal; a demultiplexer forextracting a broadcast stream including at least one program and programtable information representing the broadcast stream, from thedemodulated broadcast signal; a controller for obtaining linkinformation for linking to additional information on a channel orprogram in the broadcast stream by using the extracted program tableinformation; and a network interface unit for receiving the additionalinformation through an access to an Internet service corresponding tothe obtained link information.
 21. The device according to claim 20,wherein the receiver receives the additional information by using an NRTservice corresponding to the obtained link information; and the NRTservice uses a File Delivery over Unidirectional Transport (FLUTE)method according to a Digital Storage Media-Command & Control (DSM-CC)protocol.
 22. (canceled)
 23. (canceled)
 24. (canceled)
 25. A method ofreceiving a broadcast signal, comprising: extracting a broadcast streamincluding at least one program and program table informationrepresenting the broadcast stream, from the broadcast signal; obtaininglink information from the extracted program table information; receivingadditional information on a channel or program in the broadcast streamby using an NRT service or Internet service corresponding to the linkinformation; and displaying the received additional information.
 26. Themethod according to claim 25, wherein the displaying of the additionalinformation comprises displaying at least one of an image received usingan internet URL in the link information, an image received using an NRTservice ID and content ID in the link information, and a text obtainedusing an ETT in the program table information.
 27. The method accordingto claim 25, wherein in the case of a web browsing available receiver, ascreen for displaying the additional information is configured using anHTML page received according to the link information.
 28. (canceled) 29.(canceled)
 30. (canceled)